7. Spirits are not, as often imagined, separate beings within creation. They are souls of those who used to live on the earth or on other worlds, stripped of their corporeal envelope. Whoever believes in the existence of the soul after the death of the body must therefore also believe in the existence of spirits. To deny spirits is to deny the soul.
8. Generally speaking, people have a mistaken idea about the make-up of spirits. They are not, as some believe, vague and indefinite beings, nor are they flames like will-o'-the-wisps or ghosts like in the tales about souls from another world. They are beings like we are, with a body like ours, but fluidic and invisible in its normal state.
9. While the soul is united to the body during life, it possesses a two-fold envelope: one heavy, coarse and destructible, which is the body; the other fluidic, light and indestructible, called the perispirit.
10. Thus, in the human being there are three essential components: 1) the soul or spirit, which is the intelligent principle that harbors the thought, will and moral sense; 2) the body, which is the material envelope that enables the spirit to relate to the exterior world; and 3) the perispirit, which is the fluidic, light, imponderable envelope that serves as the connection and intermediary between the spirit and the body.
11. When the outer envelope is spent and can no longer function, it succumbs and the spirit rids itself of it like the fruit rids itself of its husk, the tree of its bark, the snake of its skin; in other words, as if it were taking off an old and useless garment. This is what is called death.
12. Death is nothing but the destruction of the material envelope; the soul abandons it like a butterfly leaving its chrysalis; however, it retains its fluidic body or perispirit.
13. The body's death frees the spirit from the envelope that had bound it to the earth and made it suffer; once freed of this burden, it possesses only its ethereal body, which allows it to travel space and traverse distances at the speed of thought.
14. The union of the soul, perispirit and physical body comprise the human being; the soul and perispirit apart from the body comprise the being called the spirit.
Note: The soul is thus a simple being; the spirit, a two-fold being and the human being, a three-fold being. Hence, it would be more precise to keep the word soul to designate the intelligent principle, and the word spirit to refer to the semi-material being formed from this principle plus the fluidic body. However, since one cannot conceive of the intelligent principle separate from all matter, or the perispirit not being animated by the intelligent principle, the terms soul and spirit are usually employed interchangeably. It is the appearance only that consists in taking the part for the whole, in the same way that one says that a town is populated by so many souls, or a settlement by so many houses. Philosophically, however, it is essential to differentiate between them.
15. Spirits clothed with physical bodies comprise humankind or the visible, corporeal world; when they are rid of these bodies, they make up the spirit or invisible world. They populate the space in the midst of which we live, without our even suspecting it, just as we used to live in the midst of the world of the infinitesimal without suspecting it before the microscope was invented.
16. Spirits are not, therefore, abstract, vague and indefinite beings, but concrete, circumscribed beings, who, if visible, would resemble humans; thus, it follows that, if at some given moment, the veil hiding them were to be lifted, they would form an entire population around us.
17. Spirits retain all the perceptions they had while on earth, but to a higher degree because their faculties are no longer deadened by matter. They experience sensations unknown to us; they see and hear things that our limited senses do not enable us to see or hear. For them there is no darkness, except for those whose punishment requires them to be in darkness temporarily. All our thoughts reverberate within them and they can read them like an open book. What we may be able to hide from a living person cannot be hidden once that person becomes a spirit.
18. Spirits are everywhere: in our midst and at our side, rubbing elbows with us and observing us constantly. Due to their continued presence amongst us, spirits are the agents of diverse phenomena; they perform an important role in our mental world and to a certain degree, in our physical world; consequently, they are one of the forces of nature.
19. Once the survival of the soul or spirit after death is accepted, it is reasonable to accept the survival of affectionate relationships; otherwise, the souls of our relatives and friends would be lost forever to us.
Since spirits can go everywhere, it is also reasonable to assume that those who used to love us during their life on earth continue to love us after death; that they can approach us, desiring to communicate with us by utilizing the means at their disposal. Experience has confirmed this fact.
In effect, experience has shown that spirits hold on to the .serious relationships they had while on earth and that they take delight in coming to those whom they loved, especially when they are attracted by the affectionate thoughts and sentiments sent to them; on the other hand, they are indifferent toward those who show indifference toward them.
20. Spiritism's objective is to verify and study the manifestations of spirits, their faculties, their happy or unhappy conditions, and their future; in other words, to know about the spirit world. Because such manifestations have been confirmed, the result has been the irrefutable proof of the existence of the soul, its survival after the body and its individuality after death, i.e., the future life. Consequently, it is the negation of materialist doctrines, not only by means of reason but by the facts.
21. A more or less normal idea held by persons who are not familiar with Spiritism is the belief that spirits must know all things and. possess supreme wisdom simply because they are free of matter. This is a serious mistake.
Since spirits are merely the souls of human beings, they do not suddenly reach perfection upon leaving their earthly envelope. The spirit's progress only occurs over time, and it is only successively that it gets rid of its imperfections and acquires the knowledge it lacks. It would also be illogical to believe that the spirit of a primitive or of a criminal could suddenly become wise and virtuous, just as it would be contrary to God's justice to believe that it would remain unevolved forever.
Since there are humans of all degrees of knowledge and ignorance, goodness and malice, the same applies to spirits. There are those who are only frivolous and playful; others who are deceitful, fraudulent, hypocritical, evil and vindictive, and still others who are possessed of sublime virtues and wisdom unknown upon the earth. Such diversity in the character of spirits is one of the most important points to consider because it explains the good or evil nature of the communications that may be received, and it is especially important to be able to distinguish between them.